The subject matter herein relates generally to matter herein relates generally to contacts for use in sockets for interconnecting two electronic components.
Sockets are used to interconnect two electronic components, such as an integrated circuit (IC) component and a printed circuit board (PCB). The sockets typically include an array of contacts held by an insulative socket body. Some known sockets have cantilever beam designs for the contacts. Other known sockets use spring loaded contacts.
Known sockets are not without disadvantages. For example, there is a desire to provide shielding for high speed signal contacts. Typically the sockets provide ground contacts in an array interspersed between corresponding signal contacts to provide shielding for such signal contacts. Providing such ground contacts uses valuable real estate in the socket. For example, some sockets may include 30%-50%, or more, of the contacts as ground contacts.
A need remains for a socket that provides high density and shielding for the signal contacts of the socket.
In one embodiment, a socket connector is provided that includes an interconnect assembly having an array of contacts being compressible in a vertical direction and shielding springs surrounding corresponding contacts and being compressible in the vertical direction with the contacts. The shielding springs are electrically grounded and provide electrical shielding for the contacts.
Optionally, the shielding springs may provide 360° shielding around individual corresponding contacts. The shielding springs may be captured between a conductive upper sheet and a conductive lower sheet with the shielding springs electrically connected to the upper and lower sheets to create electrical paths between the upper and lower sheets. The contacts may include upper contacts and lower contacts coupled to corresponding upper contacts with the upper contacts being movable with respect to the lower contacts and the upper contacts engaging the corresponding lower contacts interior of the corresponding shielding springs. The shielding springs may be coil springs helically surrounding corresponding contacts.
In another embodiment, a socket connector is provided including a socket housing having a socket chamber, and an interconnect assembly received in the socket chamber. The interconnect assembly includes an upper sheet that is conductive and has openings therethrough and a lower sheet spaced apart from the upper sheet with a space therebetween that is conductive and has openings therethrough. Upper contact assemblies are received in corresponding openings in the upper sheet. The upper contact assemblies have upper contacts and upper holders that hold the upper contacts and that are coupled to the upper sheet. Lower contact assemblies are received in corresponding openings in the lower sheet. The lower contact assemblies have lower contacts and lower holders that hold the lower contacts and that are coupled to the lower sheet. The lower contacts are electrically connected to corresponding upper contacts within the space. Shielding springs are received in the space and are electrically connected to the upper sheet and the lower sheet. The shielding springs create electrical paths between the upper sheet and the lower sheet. The shielding springs surround corresponding upper contacts and lower contacts to provide electrical shielding for such upper and lower contacts.
In a further embodiment, a method of assembling a socket connector includes positioning a plurality of upper contact assemblies into corresponding openings in an upper sheet, positioning a plurality of lower contact assemblies into corresponding openings in a lower sheet, and positioning a plurality of shielding springs between the upper sheet and the lower sheet with the shielding springs providing electrical paths between the upper sheet and the lower sheet. The shielding springs are positioned to surround corresponding upper and lower contact assemblies to provide electrical shielding for such upper and lower contact assemblies.
In an exemplary embodiment, the socket connector 100 is mated to the first electronic component 102 at a separable mating interface. The socket connector 100 may be repeatedly mated and unmated with the first electronic component 102 or similar electronic components. In an exemplary embodiment, the socket connector 100 may define a test socket for testing an integrated circuit (IC) component or similar type of component. The IC components may be repeatedly tested and removed from the socket connector 100.
The socket connector 100 may be permanently or temporarily coupled to the second electronic component 104 according to various embodiments. For example, solder balls may be provided along the mating interface between the socket connector 100 and the second electronic component 104 to couple the socket connector 100 to the second electronic component 104. Alternatively, the socket connector 100 may be mated to the second electronic component 104 at a separable interface.
The socket connector 100 includes a socket housing 106. The socket housing 106 includes a socket chamber 108 that holds an interconnect assembly 110. The socket chamber 108 is open at a first surface 112 for receiving the first electronic component 102. The interconnect assembly 110 is exposed through the opening at the first surface 112 for mating with the first electronic component 102. The socket housing 106 has a second surface 114. The socket housing 106 may be mounted to the second electronic component 102 at the second surface 114. Alternatively, the second electronic component 102 may be received into the socket chamber 108 through an opening at the second surface 114 for mating with the interconnect assembly 110. In an exemplary embodiment, the socket housing 106 includes an upper frame 116 and a lower frame 118 that are coupled together. The interconnect assembly 110 is held between the upper and lower frames 116, 118.
The interconnect assembly 110 includes an array of contacts 120 that are configured to be mated to corresponding conductors, such as pads, of the electronic components 102, 104 to electrically connect the electronic components 102, 104. The contacts 120 are held by the socket housing 106 in the socket chamber 108. The socket connector 100 may hold any number of contacts 120. The pattern or arrangement of the contacts 120 may correspond with the corresponding contacts or pads on the first and second electronic components 102, 104 to ensure that the contacts 120 are mated to corresponding circuits of the first and second electronic components 102, 104.
In an exemplary embodiment, the contacts 120 are designed to have a tight pitch between adjacent contacts 120. In an exemplary embodiment, the contacts 120 are all signal contacts configured to convey data signals. The interconnect assembly 110 provides electrical shielding for each of the contacts 120 individually such that there is no need for using a subset (e.g. 30-50%) of the contacts as ground contacts to provide electrical shielding between signal contacts. The contacts 120 are designed to be deflectable at the first surface 112 and/or the second surface 114 for mating with the first electronic component 102 and/or the second electronic component 104. The contacts 120 may be designed to have a low compression load for mating the first and/or second electronic components 102, 104 with the socket 100. In an exemplary embodiment, the contacts 120 are designed to be compressible vertically such that the ends of the contacts 120 compress in line with the loading force of the first electronic component 102 and/or the second electronic component 104.
The interconnect assembly 110 includes an upper conductor 130, a lower conductor 132, a plurality of upper contact assemblies 134, a plurality of lower contact assemblies 136 and a plurality of shielding springs 138. One of the shielding springs 138 has been removed to illustrate the upper and lower contact assemblies 134, 136. In the illustrated embodiment, the upper and lower conductors 130, 132 are defined by upper and lower sheets of conductive material, and may be referred to hereinafter as an upper sheet 130 and a lower sheet 132. The upper and/or lower conductors 130, 132 may have different forms in alternative embodiments. For example, the upper conductor 130 may be manufactured from many pieces or parts, such as where portions of the contact assemblies 134 define portions of the upper conductor 130.
The shielding springs 138 are electrically connected to the upper sheet 130 and the lower sheet 132 creating electrical paths between the upper sheet 130 and the lower sheet 132. The shielding springs 138 surround corresponding upper and lower contact assemblies 134, 136 to provide electrical shielding for such upper and lower contact assemblies 134, 136. The upper sheet 130 is a planar structure manufactured from a conductive material, such as aluminum.
The upper sheet 130 includes a plurality of openings 140 extending therethrough. The openings 140 receive corresponding upper contact assemblies 134. The upper sheet 130 includes an outer surface 142 that faces outward and an inner surface 144 that faces inward opposite the outer surface 142. The shielding springs 138 engage the inner surface 144. The shielding springs 138 are electrically connected to the upper sheet 130 at the inner surface 144. The shielding springs 138 are biased against the upper sheet 130 at the inner surface 144.
The lower sheet 132 includes a plurality of openings 150. The openings receive corresponding lower contact assemblies 136. The lower sheet 132 includes an outer surface 152 that faces outward and an inner surface 154 that faces inward. The shielding springs 138 engage the inner surface 154. The shielding springs 138 are electrically connected to the lower sheet 132 at the inner surface 144. The shielding springs 138 are biased against the lower sheet 132 at the inner surface 154.
The upper and lower contact assemblies 134, 136 define the contacts 120 and include dielectric holders to hold the contacts 120. The contacts 120 are electrically isolated from the upper and lower sheets 130, 132 by the dielectric holders of the upper and lower contact assemblies 134, 136, respectively.
In an exemplary embodiment, the upper sheet 130 includes a plurality of beams 160 at the openings 140. The beams 160 may be stamped into the upper sheet 130. The beams 160 engage the upper contact assemblies 134. The beams 160 are deflectable and allow relative movement between the upper contact assemblies 134 and the upper sheet 130. For example, the beams 160 may provide approximately 1 millimeter of movement of the upper contact assembly 134 with respect to the upper sheet 130. Such movement allows for alignment of the contacts 120 with the first electrical component 102 (shown in
The lower sheet 132 includes a plurality of beams 162 at the openings 140. The beams 162 may be stamped into the lower sheet 132. The beams 162 engage the lower contact assemblies 136. The beams 162 are deflectable and allow relative movement between the lower contact assemblies 136 and the lower sheet 132. For example, the beams 162 may provide approximately 1 millimeter of movement of the lower contact assembly 136 with respect to the lower sheet 132. Such movement allows for alignment of the contacts 120 with the second electrical component 104 (shown in
The upper sheet 130 is separated from the lower sheet 132 by a distance 164 that defines a space 166. Portions of the upper and lower contact assemblies 134, 136 are received in the space 166. The shielding springs 138 are positioned within the space 166. The upper sheet 130 is movable with respect to the lower sheet 132, such as during mating of the socket connector 100 to the first electronic component 102 and/or the second electronic component 104 (shown in
The shielding springs 138 are electrically conductive. For example, the shielding springs 138 may be coated with a conductive coating, such as a silver coating or plating, to enhance the electrical conductivity of the shielding springs 138. The shielding springs 138 engage both the upper sheet 130 and the lower sheet 132 to create electrical paths therebetween. In an exemplary embodiment, the upper sheet 130 and/or the lower sheet 132 may be electrically grounded, and the shielding springs 138, which are electrically connected to the upper and lower sheets 130, 132, are likewise electrically grounded. Such grounding of the shielding springs 138 allows the shielding springs 138 to provide electrical shielding for the contacts 120. In an exemplary embodiment, the shielding springs 138 are coil springs. The shielding springs 138 extend along helical paths surrounding corresponding contacts 120. The shielding springs 138 provide 360° shielding around individual corresponding contacts 120. Optionally, at least some of the contacts 120 may be electrically grounded to the upper conductor 130 and/or the lower conductor 132, such as by using grounding tabs connected thereto or extending therefrom that directly engage the upper conductor 130 and/or lower conductor 132, such as by extending to an exterior of the upper contact assembly 134 and/or the lower contact assembly 136.
The upper contact assembly 134 includes an upper contact 172 and an upper holder 174 that holds the upper contact 172. The upper contact 172 defines a portion of the contact 120. The upper contact 172 has a mating end 176 and a terminating end 178. The mating end 176 defines a separable mating interface for mating with a corresponding conductor, such as a pad, of the first electronic component 102 (shown in
The upper holder 174 is manufactured from a dielectric material, such as a plastic material. The upper holder 174 includes an alignment rib 182 for aligning the upper holder 174 with the opening 140 in the upper sheet 130. For example, the upper sheet 130 may include an alignment slot 184 that receives the alignment rib 182. The upper holder 174 includes an outer flange 186 and an inner flange 188. The upper holder 174 is received in the opening 140 such that the upper sheet 130 is captured between the outer flange 186 and the inner flange 188. The upper holder 174 has a base 190 positioned interior of the inner flange 188. The base 190 is configured to be positioned in the space 166 (shown in
The terminating end 178, in the illustrated embodiment, constitutes a tuning fork connection for connecting to the lower contact 180. Other types of interfaces may be provided at the terminating end 178 for electrically connecting the upper contact 172 to the lower contact 180.
The lower contact assembly 136 includes the lower contact 180 and a lower holder 194 that holds the lower contact 180. The lower contact 180 defines a portion of the contact 120. The lower contact 180 has a mating end 196 and a terminating end 198. The mating end 196 defines a separable mating interface for mating with a corresponding conductor, such as a pad, of the second electronic component 104 (shown in
The lower holder 194 is manufactured from a dielectric material, such as a plastic material. The lower holder 194 includes an alignment rib 202 for aligning the lower holder 194 with the opening 150 in the lower sheet 132. For example, the lower sheet 132 may include an alignment slot 204 that receives the alignment rib 202. The lower holder 194 includes an outer flange 206 and an inner flange 208. The lower holder 194 is received in the opening 150 such that the lower sheet 132 is captured between the outer flange 206 and the inner flange 208. The lower holder 194 has a base 210 positioned interior of the inner flange 208. The base 210 is configured to be positioned in the space 166 (shown in
The terminating end 198, in the illustrated embodiment, constitutes a tuning fork connection for connecting to the upper contact 172. Other types of interfaces may be provided at the terminating end 198 for electrically connecting the lower contact 180 to the upper contact 172.
At step 232, the upper holders 174 are positioned in the openings 140 of the upper sheet 130. The upper holders 174 may be molded in place in the upper sheet 130. Alternatively, the upper holders 174 may be pre-molded or pre-manufactured and then loaded into the openings 140. Other processes may be used to position the upper holders 174 and the upper sheet 130.
At step 234, the upper contacts 172 are loaded into the upper holders 174. For example, the upper contacts 172 may be stitched into the upper holders 174. In an alternative embodiment, the upper contact 172 may be loaded into the upper holders 174 by other processes. In other alternative embodiments, the upper holder 174 may be molded around the upper contacts 172 prior to loading the upper holders 174 into the upper sheet 130. An upper assembly 224 is defined by the upper sheet 130 and the upper contact assemblies 134.
At step 236, the lower sheet 132 is provided. The lower holders 194 are positioned in the openings 150 in the lower sheet 132. Optionally, the lower holders 194 may be molded in place in the lower sheet 132. Alternatively, the lower holders 194 may be pre-molded or pre-manufactured and then loaded into the openings 150 in the lower sheet 132.
At step 238, the lower contacts 180 are loaded into the lower holder 194. The lower contacts 180 may be stitched into the lower holders 194. The lower contacts 180 may be loaded into the lower holders 194 by other processes in alternative embodiments. In some alternative embodiments, the lower holders 194 may be molded around the lower contacts 180 prior to loading the lower holders 194 into the lower sheet 132. A lower assembly 226 is defined by the lower sheet 132 and the lower contact assemblies 136.
At step 240, the lower assembly 226 is loaded into the lower frame 118. The lower assembly 226 is loaded into the lower frame 118 such that the terminating ends 198 and the bases 210 are upward facing and exposed in the socket chamber 108.
At step 242, the shielding springs 138 are positioned in the socket chamber 108 around the corresponding lower contacts 136. The lower edges 222 (shown in
At step 244, the upper assembly 224 is positioned over the lower assembly 226 and the shielding springs 138. The upper contact assemblies 134 are received in corresponding shielding springs 138. The upper assembly 224 is positioned such that the mating ends 176 (shown in
At step 246, the upper frame 116 is positioned over the interconnect assembly 110 and the lower frame 118. The upper frame 116 may be secured to the lower frame 118, such as by using fasteners or other securing means. The upper frame 116 and the lower frame 118 capture the inner connect assembly within the socket chamber 108. The socket housing 106 may be mounted to the second electrical component 104 (shown in
At step 256 the lower sheet 132 is provided with the openings 150. At step 258, the lower contact assemblies 136 are positioned in the corresponding openings 150 in the lower sheet 132. For example, the lower contact assemblies 136 may be pressed into the openings 150.
At step 260, the lower assembly 226 is loaded into the lower frame 118. The lower assembly 226 is loaded into the lower frame 118 such that the terminating ends 198 and the bases 210 are upward facing and exposed in the socket chamber 108.
At step 262, the shielding springs 138 are positioned in the socket chamber 108 around the corresponding lower contacts 136. The lower edges 222 (shown in
At step 264, the upper assembly 224 is positioned over the lower assembly 226 and the shielding springs 138. The upper contact assemblies 134 are received in corresponding shielding springs 138. The upper assembly 224 is positioned such that the mating ends 176 (shown in
At step 266, the upper frame 116 is positioned over the interconnect assembly 110 and the lower frame 118. The upper frame 116 may be secured to the lower frame 118, such as by using fasteners or other securing means. The upper frame 116 and the lower frame 118 capture the inner connect assembly within the socket chamber 108. The socket housing 106 may be mounted to the second electrical component 104 (shown in
The lower chamber 272 is defined between the second surface 114 and the shoulder 274. Optionally, the lower frame 118 may include a shoulder 276 at or near the second surface 114. The interconnect assembly 110 is positioned in the lower chamber 272 between the shoulders 274, 276. In an exemplary embodiment, the lower sheet 132 rests on the lower shoulder 276, while the upper sheet 130 is pressed against the upper shoulder 274 by the shielding springs 138. Optionally, portions of the lower contact assemblies 136 may extend to or beyond the second surface 114 for mounting to the second electronic component 104. For example, solder balls 278 may be provided at the mating ends 196 of the lower contacts 180. The solder balls 278 may extend to or beyond a second surface 114 for mounting to the second electronic component 104. In an alternative embodiment, rather than having solder balls 278, the mating ends 196 may extend to or beyond the second surface 114 for direct engagement with the second electronic component 104. For example, the mating ends 196 may define a separable mating interface with the second electronic component 104.
When the first electronic component 102 is loaded into the upper chamber 270, the interconnect assembly 110 may be compressed into the lower chamber 272. For example, pressure on the upper contact assemblies 134 from the first electronic component 102 may press the upper sheet 130 away from the shoulder 274. The shielding springs 138 impart a spring force in an upward direction against the upper sheet 130, which presses the upper contact assemblies 134 against the first electronic component 102 to maintain an electrical connection between the interconnect assembly 110 and the first electronic component 102. The beams 160 may allow additional, independent movement of each upper contact assembly 134 to accommodate for manufacturing tolerances, bowing of the upper sheet 130 and/or tilting of the upper sheet 130.
The socket connector 400 includes a socket housing 406. The socket housing 406 includes a socket chamber 408 that holds an interconnect assembly 410. The interconnect assembly 410 includes an array of contacts 420 that are configured to be mated to corresponding conductors, such as pads, of corresponding electronic components (not shown). The interconnect assembly 410 includes an upper conductor 430, defined at least in part by a conductive metal sheet 431. The upper conductor 430 includes an opening 432. The upper conductor 430 may be electrically grounded, such as to the electronic component.
The interconnect assembly 410 includes a plurality of upper contact assemblies 434 received in the opening 432. In an exemplary embodiment, portions of the upper contact assemblies 434 may be electrically conductive and may define portions of the upper conductor 430. The upper contact assemblies 434 are interlocked. For example, the upper contact assemblies 434 may be interdigitated. The upper contact assemblies 434 may be rotationally constrained. Optionally, the upper contact assemblies 434 may have at least one degree of freedom to move relative to other upper contact assemblies 434. For example, the upper contact assemblies 434 may be horizontally locked, but free to move independently in a vertical direction. In an exemplary embodiment, the upper contact assemblies 434 are hexagonally shaped to interlock adjacent upper contact assemblies 434 together. The opening 432 is shaped to interlock with the upper contact assemblies 434. Optionally, the upper contact assemblies 434 may fit snuggly within the opening 432. Optionally, each of the upper contact assemblies 434 may be pressed against at least one adjacent upper contact assembly 434. Conductive portions of the upper contact assemblies 434 may engage each other and be electrically connected to each other and the upper sheet 431.
The upper contact assembly 434 includes an upper contact 472 and an upper holder 474 that holds the upper contact 472. The upper contact 472 defines a portion of the contact 420. The upper holder 474 is manufactured from a dielectric material, such as a plastic material. In an exemplary embodiment, a conductive cap 476 is provided on the upper holder 474. The conductive cap 476 may be a separate metal piece that is coupled to the upper holder 474. Alternatively, the conductive cap 476 may be a plating or coating on the upper holder 474. The conductive cap 476 is provided along side edges 478 of the upper holder 474, such that the conductive cap 476 may be electrically coupled to an adjacent upper contact assembly 436 and/or the upper sheet 431 (shown in
The lower contact assembly 436 includes the lower contact 480 and a lower holder 494 that holds the lower contact 480. The lower contact assembly 436 may be similar to the lower contact assembly 136 (shown in
The transmission units 470 are loaded into the socket chamber 408 over the lower conductor 440. Optionally, the transmission units 470 may be loaded into the socket chamber 408 with the lower conductor 440. Side springs 490 are loaded into the socket chamber 408 in the space between the lower conductor 440 and the upper conductor 430. The side springs 490 are electrically conductive and electrically couple the upper and lower conductors 430, 440. The shielding springs 438 extend between the upper and lower conductors 430, 440. The shielding springs 438 electrically couple the upper and lower conductors 430, 440.
The upper contact assemblies 434 are interlocked within the opening 432. The conductive caps 476 of the upper contact assemblies 434 engage each other and/or the upper sheet 431 to electrically connect the conductive caps 476 to each other and to the upper sheet 431. The shielding springs 438 are electrically connected to the upper sheet 431 via the conductive caps 476. The shape of the upper contact assemblies 434 interlock the upper contact assemblies 434 with each other and the upper sheet 431. In an exemplary embodiment, the upper contact assemblies 434 are compressible vertically when mated to the electronic components. Optionally, the upper sheet 431 may be compressed vertically when mated to the electronic components.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
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